. Advertisement .
..3..
. Advertisement .
..4..
I am trying to write a programs that returns an invalid answer. I don’t know where the incorrect command is in the “org hibernate exception sqlgrammarexception could not extract resultset.”
My detail is:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.password">1234</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/test</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<mapping class="com.util.Product"/>
</session-factory>
</hibernate-configuration
entity class
@Entity
@Table(name="productdetails")
public class Product implements Serializable {
@Id
@Column(name="product-id")
private int id;
@Column(name="product-name")
private String name;
@Column(name="product-description")
private String description;
@Column(name="product-price")
private float price;
public Product() {
super();
}
public Product(int id, String name, String description, float price) {
super();
this.id = id;
this.name = name;
this.description = description;
this.price = price;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public float getPrice() {
return price;
}
public void setPrice(float price) {
this.price = price;
}
}
public class Executingclass {
public static void main(String args[]) {
SessionFactory sessionFactory=Hibernateutil.getSessionFactory();
Session session=sessionFactory.openSession();
Product product=(Product)session.get(Product.class, 1);
System.out.println(product.getId());
System.out.println(product.getName());
System.out.println(product.getDescription());
System.out.println(product.getPrice());
}
}
public class Hibernateutil {
static SessionFactory sessionFactory=null;
static{
Configuration configuration=new Configuration();
configuration.configure();
ServiceRegistry serviceRegistry=new StandardServiceRegistryBuilder().applySettings(configuration.getProperties()).build();
sessionFactory=configuration.buildSessionFactory(serviceRegistry);
}
public static SessionFactory getSessionFactory() {
return sessionFactory;
}
}
and I end up with the warning message:
INFO: HHH000327: Error performing load command : org.hibernate.exception.SQLGrammarException: could not extract ResultSet
Exception in thread "main" org.hibernate.exception.SQLGrammarException: could not extract ResultSet
at org.hibernate.exception.internal.SQLExceptionTypeDelegate.convert(SQLExceptionTypeDelegate.java:80)
at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:49)
at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:126)
at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:112)
at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.java:91)
at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.getResultSet(AbstractLoadPlanBasedLoader.java:449)
at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeQueryStatement(AbstractLoadPlanBasedLoader.java:202)
at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeLoad(AbstractLoadPlanBasedLoader.java:137)
at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeLoad(AbstractLoadPlanBasedLoader.java:102)
at org.hibernate.loader.entity.plan.AbstractLoadPlanBasedEntityLoader.load(AbstractLoadPlanBasedEntityLoader.java:186)
at org.hibernate.persister.entity.AbstractEntityPersister.load(AbstractEntityPersister.java:4126)
at org.hibernate.event.internal.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:503)
at org.hibernate.event.internal.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:468)
at org.hibernate.event.internal.DefaultLoadEventListener.load(DefaultLoadEventListener.java:213)
at org.hibernate.event.internal.DefaultLoadEventListener.proxyOrLoad(DefaultLoadEventListener.java:275)
at org.hibernate.event.internal.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:151)
at org.hibernate.internal.SessionImpl.fireLoad(SessionImpl.java:1106)
at org.hibernate.internal.SessionImpl.access$2000(SessionImpl.java:176)
at org.hibernate.internal.SessionImpl$IdentifierLoadAccessImpl.load(SessionImpl.java:2587)
at org.hibernate.internal.SessionImpl.get(SessionImpl.java:991)
at com.util.Executingclass.main(Executingclass.java:10)
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown column 'product0_.product' in 'field list'
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)
at com.mysql.jdbc.Util.getInstance(Util.java:387)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:941)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3870)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3806)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2470)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2617)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2550)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1861)
at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1962)
at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.java:82)
... 16 more
Pls, suggest the best answer to fix it.
The cause: I think the cause of this problem is the mapping of the fields in the class is incorrect.
It is possible to use hyphens, but there is a special requirement; perhaps hibernate isn’t dealing with this correctly.
The solution: Try removing the hyphens from the schema in both the database and the
@Entity
.The stacktrace shows a line that points to the problem.
Unknown columns are a sign that something is wrong with the mapping of the classes’ fields.
This is when you realize that there is no product0_.product column. The closest thing to it is product followed by a colon. Maybe the hyphen is what gives you some trouble.
I did some internet research and found this answer from a different question. It points out that hyphens are possible but that there is a special requirement. Perhaps hibernate isn’t dealing with this properly.
To summarize, you can leave out the hyphens in both the schema and
@Entity
places.